1. The projected turbofan engine WS-6 (in my knowlidge, never entered serial production) is quite similar in size and performance to MiG-23s R-29/35 turbojets and Viggens JT-8 turbofan engines. Could it been pararel-project whit the J-9? I've also heard rumours that R-29 engine was to be reverse-engineered in china for the J-9. As i'm not very knowing of aerodynamics, so have anyone any clue wich engine would been more "ideal" for the plane. Also whit the ideal engine, whats the overall aerodynamic capapilityes of the whole desing (Tailess delta whit canards, but NO FBW-system)?
My understanding is that both engines were certainly well beyond the metallurgical capabilities of China that time. Both engines have a thrust that is right in the same range as the PW F100/AL-31F but the design heritage is at least a generation behind. Even the R-29 was pushing the boundaries for the Russians.
Between the two engines, the R-29 is probably the most likely one, at least originally, and the WS-6 may have come later. At the time the J-9 was being concieved, there was an emphasis on high altitude, high speed anti bomber interception, and that favors a turbojet design over a turbofan. Not just the diameter is smaller, which reduces the aircraft cross section, but a turbojet is generally more efficient than a turbofan at higher speeds.
2. How much did J-9 project benefited (or vice versa) from the J-8II project?
Not much at all. Both were in fact, parallel projects. The J-8II was most probably the backup in case the J-9 failed.
Could these rumours of Egybtian MiG-23s be untrue? Is there nay real evidence of any MiG-23 ever purchased by china for evaluation purposes?
Oh definitely its more than true. For evidence, look no further than the Minsk theme park and the planes displayed on the deck. The MiG-23s are in fact more than just intact, they are in mint condition still sporting their Egyptian camouflage.
Could the J-9 be scaled-down version of the J-8II and thus having MiG-23 like apperance?
No.
Or is it more like that the MiG-23 features from the same supposed egybtian MiGs finded their way to J-8II project after the J-9 was cancelled?
No. Projects were parallel.
3. When the J-9 project was started and when officically cancelled? Some sort of timeline, and how well it was pararel to J-8II? Was J-9 project "live" during the flirtations whit the west just prior to the 1989 incidence? Could there have been any proposal of western participation on this project?
Started around the late sixties and officially terminated sometime in the early eighties. It actually started as a tailed delta---with aerodynamics that was ancestral from the MiG-21---then turned into a canard delta. At some point, the concept also changed from side intakes, to a square underslung intake, no doubt the inspirational basis leading later to the J-10.
Well there are many "could there" and "would there"s but feel free to give any toughts what comes to mind (no offtopic BS) Also why do we have to focus on J-9 solely? If you have anything about other cancelled chinese aviation projects, this topic can cover them also. I try to give update from my own research concerning the matter and perhaps introduce some other chinese fighter project lime the DF series or the orginal J-10 project...
There is also the original J-12 project, of which there is actually one flying prototype built. Basically the plane uses just one of the J-6 WP-6 engines, and is only a clear weather day fighter with a round inlet nose. But even in the sixties, a radarless day fighter only no longer has any relevance, so it was cancelled. Other projects also include the original J-13, which is analogous to the Mirage F1.
